There are only two accepted portraits of William Shakespeare that are considered "official," but a portrait that's been hanging over a mantlepiece for the last 50 years could be the third. It could be worth as much as $200 million…if it is genuine. 

Can the stories about King Arthur be proven true? Was the legendary court of Camelot a real place? Join Prof. Mark Horton on his journey across Britain to prove real events and places inspired the chivalric myths. Horton scours medieval texts and archaeological sites for a new understanding of the Arthurian legends and what Britain was like after the Romans left in the fifth century.